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arXiv · 1405.3205

Ab initio quantum transport through armchair graphene nanoribbons: Streamlines in the current density

Jan Wilhelm·Michael Walz·Ferdinand Evers
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Abstract

We calculate the local current density in pristine armchair graphene nanoribbons (AGNRs) with varying width, $N_\mathrm{C}$, employing a density-functional-theory-based ab initio transport formalism. We observe very pronounced current patterns (streamlines) with threefold periodicity in $N_\mathrm{C}$. They arise as a consequence of quantum confinement in the transverse flow direction. Neighboring streamlines are separated by stripes of almost vanishing flow. As a consequence, the response of the current to functionalizing adsorbates is very sensitive to their placement: adsorbates located within the current filaments lead to strong backscattering, while adsorbates placed in other regions have almost no impact at all.

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Jan Wilhelm, Michael Walz, Ferdinand Evers. 2014-05-13. Ab initio quantum transport through armchair graphene nanoribbons: Streamlines in the current density. https://doi.org/10.1103/physrevb.89.195406

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